An infrared transient from a star engulfing a planet

Kishalay De; Morgan MacLeod; Viraj Karambelkar; Jacob E Jencson; Deepto Chakrabarty; Charlie Conroy; Richard Dekany; Anna-Christina Eilers; Matthew J Graham; Lynne A Hillenbrand; Erin Kara; Mansi M Kasliwal; S R Kulkarni; Ryan M Lau; Abraham Loeb; Frank Masci; Michael S Medford; Aaron M Meisner; Nimesh Patel; Luis Henry Quiroga-Nuñez; Reed L Riddle; Ben Rusholme; Robert Simcoe; Loránt O Sjouwerman; Richard Teague; Andrew Vanderburg

doi:10.1038/s41586-023-05842-x

An infrared transient from a star engulfing a planet

Nature. 2023 May;617(7959):55-60. doi: 10.1038/s41586-023-05842-x. Epub 2023 May 3.

Authors

Kishalay De¹, Morgan MacLeod², Viraj Karambelkar³, Jacob E Jencson⁴, Deepto Chakrabarty⁵, Charlie Conroy², Richard Dekany⁶, Anna-Christina Eilers⁵, Matthew J Graham³, Lynne A Hillenbrand³, Erin Kara⁵, Mansi M Kasliwal³, S R Kulkarni³, Ryan M Lau⁷, Abraham Loeb^{2

8}, Frank Masci⁹, Michael S Medford^{10

11}, Aaron M Meisner⁷, Nimesh Patel², Luis Henry Quiroga-Nuñez¹², Reed L Riddle⁶, Ben Rusholme⁹, Robert Simcoe⁵, Loránt O Sjouwerman¹³, Richard Teague^{2

14}, Andrew Vanderburg⁵

Affiliations

¹ Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA. [email protected].
² Center for Astrophysics/Harvard & Smithsonian, Cambridge, MA, USA.
³ Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA, USA.
⁴ Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, USA.
⁵ Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
⁶ Caltech Optical Observatories, California Institute of Technology, Pasadena, CA, USA.
⁷ NSF's National Optical-Infrared Astronomy Research Laboratory, Tucson, AZ, USA.
⁸ Black Hole Initiative, Harvard University, Cambridge, MA, USA.
⁹ IPAC, California Institute of Technology, Pasadena, CA, USA.
¹⁰ Department of Astronomy, University of California, Berkeley, Berkeley, CA, USA.
¹¹ Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
¹² Department of Aerospace, Physics and Space Sciences, Florida Institute of Technology, Melbourne, FL, USA.
¹³ National Radio Astronomy Observatory, Array Operations Center, Socorro, NM, USA.
¹⁴ Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.

PMID: 37138107
DOI: 10.1038/s41586-023-05842-x

Abstract

Planets with short orbital periods (roughly under 10 days) are common around stars like the Sun^1,2. Stars expand as they evolve and thus we expect their close planetary companions to be engulfed, possibly powering luminous mass ejections from the host star^3-5. However, this phase has never been directly observed. Here we report observations of ZTF SLRN-2020, a short-lived optical outburst in the Galactic disk accompanied by bright and long-lived infrared emission. The resulting light curve and spectra share striking similarities with those of red novae^6,7-a class of eruptions now confirmed⁸ to arise from mergers of binary stars. Its exceptionally low optical luminosity (approximately 10³⁵ erg s^-1) and radiated energy (approximately 6.5 × 10⁴¹ erg) point to the engulfment of a planet of fewer than roughly ten Jupiter masses by its Sun-like host star. We estimate the Galactic rate of such subluminous red novae to be roughly between 0.1 and several per year. Future Galactic plane surveys should routinely identify these, showing the demographics of planetary engulfment and the ultimate fate of planets in the inner Solar System.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

Abstract

Publication types

Grants and funding